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authorStephen Boyd <sboyd@kernel.org>2019-03-08 21:35:01 +0300
committerStephen Boyd <sboyd@kernel.org>2019-03-08 21:35:01 +0300
commit5dc7e84268f53f08251abe1d388a019f55ddb077 (patch)
tree6f2bd70a3e7c9f00071dca20d0714a692de74c3c /drivers/clk
parentfea0b0850aad878391b1021b3b1b4044c4ec5aaf (diff)
parentcf13f2896807d516df79d118d1e82f9d2db3c336 (diff)
downloadlinux-5dc7e84268f53f08251abe1d388a019f55ddb077.tar.xz
Merge branch 'clk-parent-rewrite' (early part) into clk-next
* 'clk-parent-rewrite' (early part): clk: Move of_clk_*() APIs into clk.c from clkdev.c clk: Inform the core about consumer devices clk: Introduce of_clk_get_hw_from_clkspec() clk: core: clarify the check for runtime PM clk: Combine __clk_get() and __clk_create_clk()
Diffstat (limited to 'drivers/clk')
-rw-r--r--drivers/clk/clk.c259
-rw-r--r--drivers/clk/clk.h23
-rw-r--r--drivers/clk/clkdev.c126
3 files changed, 230 insertions, 178 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index af3882f04080..14cbf239d9b2 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -57,6 +57,7 @@ struct clk_core {
struct clk_core *new_child;
unsigned long flags;
bool orphan;
+ bool rpm_enabled;
unsigned int enable_count;
unsigned int prepare_count;
unsigned int protect_count;
@@ -81,6 +82,7 @@ struct clk_core {
struct clk {
struct clk_core *core;
+ struct device *dev;
const char *dev_id;
const char *con_id;
unsigned long min_rate;
@@ -92,9 +94,9 @@ struct clk {
/*** runtime pm ***/
static int clk_pm_runtime_get(struct clk_core *core)
{
- int ret = 0;
+ int ret;
- if (!core->dev)
+ if (!core->rpm_enabled)
return 0;
ret = pm_runtime_get_sync(core->dev);
@@ -103,7 +105,7 @@ static int clk_pm_runtime_get(struct clk_core *core)
static void clk_pm_runtime_put(struct clk_core *core)
{
- if (!core->dev)
+ if (!core->rpm_enabled)
return;
pm_runtime_put_sync(core->dev);
@@ -223,7 +225,7 @@ static bool clk_core_is_enabled(struct clk_core *core)
* taking enable spinlock, but the below check is needed if one tries
* to call it from other places.
*/
- if (core->dev) {
+ if (core->rpm_enabled) {
pm_runtime_get_noresume(core->dev);
if (!pm_runtime_active(core->dev)) {
ret = false;
@@ -233,7 +235,7 @@ static bool clk_core_is_enabled(struct clk_core *core)
ret = core->ops->is_enabled(core->hw);
done:
- if (core->dev)
+ if (core->rpm_enabled)
pm_runtime_put(core->dev);
return ret;
@@ -3212,43 +3214,106 @@ unlock:
return ret;
}
-struct clk *__clk_create_clk(struct clk_hw *hw, const char *dev_id,
+/**
+ * clk_core_link_consumer - Add a clk consumer to the list of consumers in a clk_core
+ * @core: clk to add consumer to
+ * @clk: consumer to link to a clk
+ */
+static void clk_core_link_consumer(struct clk_core *core, struct clk *clk)
+{
+ clk_prepare_lock();
+ hlist_add_head(&clk->clks_node, &core->clks);
+ clk_prepare_unlock();
+}
+
+/**
+ * clk_core_unlink_consumer - Remove a clk consumer from the list of consumers in a clk_core
+ * @clk: consumer to unlink
+ */
+static void clk_core_unlink_consumer(struct clk *clk)
+{
+ lockdep_assert_held(&prepare_lock);
+ hlist_del(&clk->clks_node);
+}
+
+/**
+ * alloc_clk - Allocate a clk consumer, but leave it unlinked to the clk_core
+ * @core: clk to allocate a consumer for
+ * @dev_id: string describing device name
+ * @con_id: connection ID string on device
+ *
+ * Returns: clk consumer left unlinked from the consumer list
+ */
+static struct clk *alloc_clk(struct clk_core *core, const char *dev_id,
const char *con_id)
{
struct clk *clk;
- /* This is to allow this function to be chained to others */
- if (IS_ERR_OR_NULL(hw))
- return ERR_CAST(hw);
-
clk = kzalloc(sizeof(*clk), GFP_KERNEL);
if (!clk)
return ERR_PTR(-ENOMEM);
- clk->core = hw->core;
+ clk->core = core;
clk->dev_id = dev_id;
clk->con_id = kstrdup_const(con_id, GFP_KERNEL);
clk->max_rate = ULONG_MAX;
- clk_prepare_lock();
- hlist_add_head(&clk->clks_node, &hw->core->clks);
- clk_prepare_unlock();
-
return clk;
}
-/* keep in sync with __clk_put */
-void __clk_free_clk(struct clk *clk)
+/**
+ * free_clk - Free a clk consumer
+ * @clk: clk consumer to free
+ *
+ * Note, this assumes the clk has been unlinked from the clk_core consumer
+ * list.
+ */
+static void free_clk(struct clk *clk)
{
- clk_prepare_lock();
- hlist_del(&clk->clks_node);
- clk_prepare_unlock();
-
kfree_const(clk->con_id);
kfree(clk);
}
/**
+ * clk_hw_create_clk: Allocate and link a clk consumer to a clk_core given
+ * a clk_hw
+ * @dev: clk consumer device
+ * @hw: clk_hw associated with the clk being consumed
+ * @dev_id: string describing device name
+ * @con_id: connection ID string on device
+ *
+ * This is the main function used to create a clk pointer for use by clk
+ * consumers. It connects a consumer to the clk_core and clk_hw structures
+ * used by the framework and clk provider respectively.
+ */
+struct clk *clk_hw_create_clk(struct device *dev, struct clk_hw *hw,
+ const char *dev_id, const char *con_id)
+{
+ struct clk *clk;
+ struct clk_core *core;
+
+ /* This is to allow this function to be chained to others */
+ if (IS_ERR_OR_NULL(hw))
+ return ERR_CAST(hw);
+
+ core = hw->core;
+ clk = alloc_clk(core, dev_id, con_id);
+ if (IS_ERR(clk))
+ return clk;
+ clk->dev = dev;
+
+ if (!try_module_get(core->owner)) {
+ free_clk(clk);
+ return ERR_PTR(-ENOENT);
+ }
+
+ kref_get(&core->ref);
+ clk_core_link_consumer(core, clk);
+
+ return clk;
+}
+
+/**
* clk_register - allocate a new clock, register it and return an opaque cookie
* @dev: device that is registering this clock
* @hw: link to hardware-specific clock data
@@ -3283,7 +3348,8 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
core->ops = hw->init->ops;
if (dev && pm_runtime_enabled(dev))
- core->dev = dev;
+ core->rpm_enabled = true;
+ core->dev = dev;
if (dev && dev->driver)
core->owner = dev->driver->owner;
core->hw = hw;
@@ -3323,17 +3389,27 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
INIT_HLIST_HEAD(&core->clks);
- hw->clk = __clk_create_clk(hw, NULL, NULL);
+ /*
+ * Don't call clk_hw_create_clk() here because that would pin the
+ * provider module to itself and prevent it from ever being removed.
+ */
+ hw->clk = alloc_clk(core, NULL, NULL);
if (IS_ERR(hw->clk)) {
ret = PTR_ERR(hw->clk);
goto fail_parents;
}
+ clk_core_link_consumer(hw->core, hw->clk);
+
ret = __clk_core_init(core);
if (!ret)
return hw->clk;
- __clk_free_clk(hw->clk);
+ clk_prepare_lock();
+ clk_core_unlink_consumer(hw->clk);
+ clk_prepare_unlock();
+
+ free_clk(hw->clk);
hw->clk = NULL;
fail_parents:
@@ -3604,20 +3680,7 @@ EXPORT_SYMBOL_GPL(devm_clk_hw_unregister);
/*
* clkdev helpers
*/
-int __clk_get(struct clk *clk)
-{
- struct clk_core *core = !clk ? NULL : clk->core;
-
- if (core) {
- if (!try_module_get(core->owner))
- return 0;
- kref_get(&core->ref);
- }
- return 1;
-}
-
-/* keep in sync with __clk_free_clk */
void __clk_put(struct clk *clk)
{
struct module *owner;
@@ -3651,8 +3714,7 @@ void __clk_put(struct clk *clk)
module_put(owner);
- kfree_const(clk->con_id);
- kfree(clk);
+ free_clk(clk);
}
/*** clk rate change notifiers ***/
@@ -4009,6 +4071,49 @@ void devm_of_clk_del_provider(struct device *dev)
}
EXPORT_SYMBOL(devm_of_clk_del_provider);
+/*
+ * Beware the return values when np is valid, but no clock provider is found.
+ * If name == NULL, the function returns -ENOENT.
+ * If name != NULL, the function returns -EINVAL. This is because
+ * of_parse_phandle_with_args() is called even if of_property_match_string()
+ * returns an error.
+ */
+static int of_parse_clkspec(const struct device_node *np, int index,
+ const char *name, struct of_phandle_args *out_args)
+{
+ int ret = -ENOENT;
+
+ /* Walk up the tree of devices looking for a clock property that matches */
+ while (np) {
+ /*
+ * For named clocks, first look up the name in the
+ * "clock-names" property. If it cannot be found, then index
+ * will be an error code and of_parse_phandle_with_args() will
+ * return -EINVAL.
+ */
+ if (name)
+ index = of_property_match_string(np, "clock-names", name);
+ ret = of_parse_phandle_with_args(np, "clocks", "#clock-cells",
+ index, out_args);
+ if (!ret)
+ break;
+ if (name && index >= 0)
+ break;
+
+ /*
+ * No matching clock found on this node. If the parent node
+ * has a "clock-ranges" property, then we can try one of its
+ * clocks.
+ */
+ np = np->parent;
+ if (np && !of_get_property(np, "clock-ranges", NULL))
+ break;
+ index = 0;
+ }
+
+ return ret;
+}
+
static struct clk_hw *
__of_clk_get_hw_from_provider(struct of_clk_provider *provider,
struct of_phandle_args *clkspec)
@@ -4024,36 +4129,26 @@ __of_clk_get_hw_from_provider(struct of_clk_provider *provider,
return __clk_get_hw(clk);
}
-struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec,
- const char *dev_id, const char *con_id)
+static struct clk_hw *
+of_clk_get_hw_from_clkspec(struct of_phandle_args *clkspec)
{
struct of_clk_provider *provider;
- struct clk *clk = ERR_PTR(-EPROBE_DEFER);
- struct clk_hw *hw;
+ struct clk_hw *hw = ERR_PTR(-EPROBE_DEFER);
if (!clkspec)
return ERR_PTR(-EINVAL);
- /* Check if we have such a provider in our array */
mutex_lock(&of_clk_mutex);
list_for_each_entry(provider, &of_clk_providers, link) {
if (provider->node == clkspec->np) {
hw = __of_clk_get_hw_from_provider(provider, clkspec);
- clk = __clk_create_clk(hw, dev_id, con_id);
- }
-
- if (!IS_ERR(clk)) {
- if (!__clk_get(clk)) {
- __clk_free_clk(clk);
- clk = ERR_PTR(-ENOENT);
- }
-
- break;
+ if (!IS_ERR(hw))
+ break;
}
}
mutex_unlock(&of_clk_mutex);
- return clk;
+ return hw;
}
/**
@@ -4066,10 +4161,62 @@ struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec,
*/
struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec)
{
- return __of_clk_get_from_provider(clkspec, NULL, __func__);
+ struct clk_hw *hw = of_clk_get_hw_from_clkspec(clkspec);
+
+ return clk_hw_create_clk(NULL, hw, NULL, __func__);
}
EXPORT_SYMBOL_GPL(of_clk_get_from_provider);
+struct clk_hw *of_clk_get_hw(struct device_node *np, int index,
+ const char *con_id)
+{
+ int ret;
+ struct clk_hw *hw;
+ struct of_phandle_args clkspec;
+
+ ret = of_parse_clkspec(np, index, con_id, &clkspec);
+ if (ret)
+ return ERR_PTR(ret);
+
+ hw = of_clk_get_hw_from_clkspec(&clkspec);
+ of_node_put(clkspec.np);
+
+ return hw;
+}
+
+static struct clk *__of_clk_get(struct device_node *np,
+ int index, const char *dev_id,
+ const char *con_id)
+{
+ struct clk_hw *hw = of_clk_get_hw(np, index, con_id);
+
+ return clk_hw_create_clk(NULL, hw, dev_id, con_id);
+}
+
+struct clk *of_clk_get(struct device_node *np, int index)
+{
+ return __of_clk_get(np, index, np->full_name, NULL);
+}
+EXPORT_SYMBOL(of_clk_get);
+
+/**
+ * of_clk_get_by_name() - Parse and lookup a clock referenced by a device node
+ * @np: pointer to clock consumer node
+ * @name: name of consumer's clock input, or NULL for the first clock reference
+ *
+ * This function parses the clocks and clock-names properties,
+ * and uses them to look up the struct clk from the registered list of clock
+ * providers.
+ */
+struct clk *of_clk_get_by_name(struct device_node *np, const char *name)
+{
+ if (!np)
+ return ERR_PTR(-ENOENT);
+
+ return __of_clk_get(np, -1, np->full_name, name);
+}
+EXPORT_SYMBOL(of_clk_get_by_name);
+
/**
* of_clk_get_parent_count() - Count the number of clocks a device node has
* @np: device node to count
diff --git a/drivers/clk/clk.h b/drivers/clk/clk.h
index b02f5e604e69..553f531cc232 100644
--- a/drivers/clk/clk.h
+++ b/drivers/clk/clk.h
@@ -5,31 +5,36 @@
*/
struct clk_hw;
+struct device;
+struct of_phandle_args;
#if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK)
-struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec,
- const char *dev_id, const char *con_id);
+struct clk_hw *of_clk_get_hw(struct device_node *np,
+ int index, const char *con_id);
+#else /* !CONFIG_COMMON_CLK || !CONFIG_OF */
+static inline struct clk_hw *of_clk_get_hw(struct device_node *np,
+ int index, const char *con_id)
+{
+ return ERR_PTR(-ENOENT);
+}
#endif
#ifdef CONFIG_COMMON_CLK
-struct clk *__clk_create_clk(struct clk_hw *hw, const char *dev_id,
- const char *con_id);
-void __clk_free_clk(struct clk *clk);
-int __clk_get(struct clk *clk);
+struct clk *clk_hw_create_clk(struct device *dev, struct clk_hw *hw,
+ const char *dev_id, const char *con_id);
void __clk_put(struct clk *clk);
#else
/* All these casts to avoid ifdefs in clkdev... */
static inline struct clk *
-__clk_create_clk(struct clk_hw *hw, const char *dev_id, const char *con_id)
+clk_hw_create_clk(struct device *dev, struct clk_hw *hw, const char *dev_id,
+ const char *con_id)
{
return (struct clk *)hw;
}
-static inline void __clk_free_clk(struct clk *clk) { }
static struct clk_hw *__clk_get_hw(struct clk *clk)
{
return (struct clk_hw *)clk;
}
-static inline int __clk_get(struct clk *clk) { return 1; }
static inline void __clk_put(struct clk *clk) { }
#endif
diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c
index 4cfe39636105..8c4435c53f09 100644
--- a/drivers/clk/clkdev.c
+++ b/drivers/clk/clkdev.c
@@ -27,105 +27,6 @@
static LIST_HEAD(clocks);
static DEFINE_MUTEX(clocks_mutex);
-#if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK)
-static struct clk *__of_clk_get(struct device_node *np, int index,
- const char *dev_id, const char *con_id)
-{
- struct of_phandle_args clkspec;
- struct clk *clk;
- int rc;
-
- rc = of_parse_phandle_with_args(np, "clocks", "#clock-cells", index,
- &clkspec);
- if (rc)
- return ERR_PTR(rc);
-
- clk = __of_clk_get_from_provider(&clkspec, dev_id, con_id);
- of_node_put(clkspec.np);
-
- return clk;
-}
-
-struct clk *of_clk_get(struct device_node *np, int index)
-{
- return __of_clk_get(np, index, np->full_name, NULL);
-}
-EXPORT_SYMBOL(of_clk_get);
-
-/*
- * Beware the return values when np is valid, but no clock provider is found.
- * If name == NULL, the function returns -ENOENT.
- * If name != NULL, the function returns -EINVAL. This is because __of_clk_get()
- * is called even if of_property_match_string() returns an error.
- */
-static struct clk *__of_clk_get_by_name(struct device_node *np,
- const char *dev_id,
- const char *name)
-{
- struct clk *clk = ERR_PTR(-ENOENT);
-
- /* Walk up the tree of devices looking for a clock that matches */
- while (np) {
- int index = 0;
-
- /*
- * For named clocks, first look up the name in the
- * "clock-names" property. If it cannot be found, then
- * index will be an error code, and of_clk_get() will fail.
- */
- if (name)
- index = of_property_match_string(np, "clock-names", name);
- clk = __of_clk_get(np, index, dev_id, name);
- if (!IS_ERR(clk)) {
- break;
- } else if (name && index >= 0) {
- if (PTR_ERR(clk) != -EPROBE_DEFER)
- pr_err("ERROR: could not get clock %pOF:%s(%i)\n",
- np, name ? name : "", index);
- return clk;
- }
-
- /*
- * No matching clock found on this node. If the parent node
- * has a "clock-ranges" property, then we can try one of its
- * clocks.
- */
- np = np->parent;
- if (np && !of_get_property(np, "clock-ranges", NULL))
- break;
- }
-
- return clk;
-}
-
-/**
- * of_clk_get_by_name() - Parse and lookup a clock referenced by a device node
- * @np: pointer to clock consumer node
- * @name: name of consumer's clock input, or NULL for the first clock reference
- *
- * This function parses the clocks and clock-names properties,
- * and uses them to look up the struct clk from the registered list of clock
- * providers.
- */
-struct clk *of_clk_get_by_name(struct device_node *np, const char *name)
-{
- if (!np)
- return ERR_PTR(-ENOENT);
-
- return __of_clk_get_by_name(np, np->full_name, name);
-}
-EXPORT_SYMBOL(of_clk_get_by_name);
-
-#else /* defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK) */
-
-static struct clk *__of_clk_get_by_name(struct device_node *np,
- const char *dev_id,
- const char *name)
-{
- return ERR_PTR(-ENOENT);
-}
-#endif
-
/*
* Find the correct struct clk for the device and connection ID.
* We do slightly fuzzy matching here:
@@ -169,7 +70,8 @@ static struct clk_lookup *clk_find(const char *dev_id, const char *con_id)
return cl;
}
-struct clk *clk_get_sys(const char *dev_id, const char *con_id)
+static struct clk *__clk_get_sys(struct device *dev, const char *dev_id,
+ const char *con_id)
{
struct clk_lookup *cl;
struct clk *clk = NULL;
@@ -180,35 +82,33 @@ struct clk *clk_get_sys(const char *dev_id, const char *con_id)
if (!cl)
goto out;
- clk = __clk_create_clk(cl->clk_hw, dev_id, con_id);
+ clk = clk_hw_create_clk(dev, cl->clk_hw, dev_id, con_id);
if (IS_ERR(clk))
- goto out;
-
- if (!__clk_get(clk)) {
- __clk_free_clk(clk);
cl = NULL;
- goto out;
- }
-
out:
mutex_unlock(&clocks_mutex);
return cl ? clk : ERR_PTR(-ENOENT);
}
+
+struct clk *clk_get_sys(const char *dev_id, const char *con_id)
+{
+ return __clk_get_sys(NULL, dev_id, con_id);
+}
EXPORT_SYMBOL(clk_get_sys);
struct clk *clk_get(struct device *dev, const char *con_id)
{
const char *dev_id = dev ? dev_name(dev) : NULL;
- struct clk *clk;
+ struct clk_hw *hw;
if (dev && dev->of_node) {
- clk = __of_clk_get_by_name(dev->of_node, dev_id, con_id);
- if (!IS_ERR(clk) || PTR_ERR(clk) == -EPROBE_DEFER)
- return clk;
+ hw = of_clk_get_hw(dev->of_node, 0, con_id);
+ if (!IS_ERR(hw) || PTR_ERR(hw) == -EPROBE_DEFER)
+ return clk_hw_create_clk(dev, hw, dev_id, con_id);
}
- return clk_get_sys(dev_id, con_id);
+ return __clk_get_sys(dev, dev_id, con_id);
}
EXPORT_SYMBOL(clk_get);